The proper working of an active safety system depends to a great extent on proper detection. Not only is the type of detector important, but also its location. An unfavourable location might not only result in so-called "false" alarms, but could also cause the detector to function improperly within the system, even thought the detector itself is perfectly OK.
Think for example of the contamination of an optical detector by product deposits. However, deposits on pressure detectors can also lead to a non-functioning system, especially with products that can cake due to moisture. Establishing the correct location is not always simple and is a job for specialists. Considerations include processes with CIP, excessive wear…
The simplest detector is the PDS detector. This is a static pressure detector based on a membrane with a switch. The absence of electronics makes this detector very reliable. Thanks to the large membrane, the detector is relatively insensitive to moderate product impact.
This detector is also equipped with a mechanical memory. All other detectors are electronic units that compare the signal of the sensors with their normal state settings. To avoid false alarms, the signal of the sensor is compared several times with the configured alarm and fault thresholds. If the sensor values are still within the alarm window after several samples, the alarm is triggered. Sample rate, sensitivity, etc. can be configured for the specific detector. Detectors such as the PDP detector are also equipped with a memory(4), so that the triggering conditions can be verified after an alarm has been triggered.
ProDetec | Fire & Gas Detection; Spark & Hot Ember Detection
ProDetec represents Simtronics Fire & Gas (previously known as Simrad Optronics), Firefly, IRMACO Group (StuvEx, ISMA & Pagg). Water Mist Engineering (WME), ETech, Fireater, Groveley Detection and ...